Recent results of the searches for Supersymmetry in final states with one or two leptons at CMS are presented. Many Supersymmetry scenarios, including the Constrained Minimal Supersymmetric extension of the Standard Model (CMSSM), predict a substantial amount of events containing leptons, while the largest fraction of Standard Model background events -which are QCD interactions -gets strongly reduced by requiring isolated leptons. The analyzed data was taken in 2011 and corresponds to an integrated luminosity of approximately L = 1 fb −1 . The center-of-mass energy of the pp collisions was √ s = 7 TeV.
The Advanced GAmma Tracking Array (AGATA) is a European project to develop and operate the next generation γ-ray spectrometer. AGATA is based on the technique of γ-ray energy tracking in electrically segmented high-purity germanium crystals. This technique requires the accurate determination of the energy, time and position of every interaction as a γ ray deposits its energy within the detector volume. Reconstruction of the full interaction path results in a detector with very high efficiency and excellent spectral response. The realisation of γ-ray tracking and AGATA is a result of many technical advances. These include the development of encapsulated highly segmented germanium detectors assembled in a triple cluster detector cryostat, an electronics system with fast digital sampling and a data acquisition system to process the data at a high rate. The full characterisation of the crystals was measured and compared with detector-response simulations. This enabled pulse-shape analysis algorithms, to extract energy, time and position, to be employed. In addition, tracking algorithms for event reconstruction were developed. The first phase of AGATA is now complete and operational in its first physics campaign. In the future AGATA will be moved between laboratories in Europe and operated in a series of campaigns to take advantage of the different beams and facilities available to maximise its science output. The paper reviews all the achievements made in the AGATA project including all the necessary infrastructure to operate and support the spectrometer
CMS is a general purpose experiment, designed to study the physics of pp collisions at 14 TeV at the Large Hadron Collider (LHC). It currently involves more than 2000 physicists from more than 150 institutes and 37 countries. The LHC will provide extraordinary opportunities for particle physics based on its unprecedented collision energy and luminosity when it begins operation in 2007.The principal aim of this report is to present the strategy of CMS to explore the rich physics programme offered by the LHC. This volume demonstrates the physics capability of the CMS experiment. The prime goals of CMS are to explore physics at the TeV scale and to study the mechanism of electroweak symmetry breaking-through the discovery of the Higgs particle or otherwise. To carry out this task, CMS must be prepared to search for new particles, such as the Higgs boson or supersymmetric partners of the Standard Model particles, from the start-up of the LHC since new physics at the TeV scale may manifest itself with modest data samples of the order of a few fb −1 or less. The analysis tools that have been developed are applied to study in great detail and with all the methodology of performing an analysis on CMS data specific benchmark processes upon which to gauge the performance of CMS. These processes cover several Higgs boson decay channels, the production and decay of new particles such as Z and supersymmetric particles, B s production and processes in heavy ion collisions. The simulation of these benchmark processes includes subtle effects such as possible detector miscalibration and misalignment. Besides these benchmark processes, the physics reach of CMS is studied for a large number of signatures arising in the Standard Model and also in theories beyond the Standard Model for integrated luminosities ranging from 1 fb −1 to 30 fb −1 . The Standard Model processes include QCD, B-physics, diffraction, detailed studies of the top quark properties, and electroweak physics topics such as the W and Z 0 boson properties. The production and decay of the Higgs particle is studied for many observable decays, and the precision with which the Higgs boson properties can be derived is determined. About ten different supersymmetry benchmark points are analysed using full simulation. The CMS discovery reach is evaluated in the SUSY parameter space covering a large variety of decay signatures.
The experimental data obtained from the reaction of 6 Li projectiles at 2A GeV on a fixed graphite target were analyzed to study the invariant mass distributions of d + π − and t + π − . Indications of a signal in the d + π − and t + π − invariant mass distributions were observed with significances of 5.3 σ and 5.0 σ , respectively, when including the production target, and 3.7 σ and 5.2 σ , respectively, when excluding the target. The estimated mean values of the invariant mass for d + π − and t + π − signal were 2059.3 ± 1.3 ± 1.7 MeV/c 2 and 2993.7 ± 1.3 ± 0.6 MeV/c 2 respectively. The lifetime estimation of the possible bound states yielding to d + π − and t + π − final states were deduced to be as 181 +30 −24 ± 25 ps and 190 +47 −35 ± 36 ps, respectively. Those final states may be interpreted as the two-body and three-body decay modes of a neutral bound state of two neutrons and a hyperon, 3 n.A hypernucleus, a subatomic system with at least one bound hyperon, is studied in order to deduce the information about fundamental hyperon (Y )-nucleon (N) and Y -Y interactions. Hypernuclei have been mainly studied by means of the missing-mass experiments with secondary-meson and primary-electron beams [1] and earlier with emulsion techniques and bubble chambers [2]. In these experiments, a variety of hypernuclei with the lightest hyperon, the hyperon, were produced and identified. However, the isospin of the produced hypernuclei is similar to that of the target nucleus in these experiments, since they are produced by the elementary process of converting one nucleon in the target nucleus into a hyperon.Information on the Λ-N interaction was already inferred from the hypernuclei in the vicinity of the β stability line * c.rappold@gsi.de † t.saito@gsi.de [3][4][5][6]. The nature of the Λ-N interaction for neutron-rich hypernuclei, in which the ΛN -ΣN coupling three-body force may play a role as described theoretically in Refs. [7-11], has not yet been studied in detail since only a few cases were observed, 10 Li [12], 7 He [13], and 6 H [14]. We thus search for other neutron-rich hypernuclei by means of induced reactions of heavy-ion beams.Neutron-and proton-rich hypernuclei can be indeed studied by using projectile fragmentation reactions of heavy-ion beams. In such reactions, a projectile fragment can capture a hyperon produced in the hot participant region to produce a hypernucleus [15][16][17][18][19]. They might also be produced in a multistage process, such as through a Fermi breakup decay of excited heavier hypernuclear spectators, possibly formed in peripheral collisions [19][20][21].We, the HypHI Collaboration, have proposed a series of experiments at the GSI Helmholtz Centre for Heavy Ion Research that would use induced reactions of stable heavy-ion beams and rare-isotope beams to produce 041001-1 0556-2813/2013/88(4)/041001 (6)
A novel experiment, aiming at demonstrating the feasibility of hypernuclear spectroscopy with heavy-ion beams, was conducted. Using the invariant mass method, the spectroscopy of hypernuclear products of 6 Li projectiles on a carbon target at 2 A GeV was performed. Signals of the Λ-hyperon and 3 Λ H and 4 Λ H hypernuclei were observed for final states of p+π − , 3 He+π − and 4 He+π − , respectively, with significance values of 6.7, 4.7 and 4.9σ. By analyzing the proper decay time from secondary vertex distribution with the unbinned maximum likelihood fitting method, their lifetime values were deduced to be 262 +56 −43 ± 45 ps for Λ, 183 +42 −32 ± 37 ps for 3 Λ H, and 140 +48 −33 ± 35 ps for 4 Λ H.
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